A chemically modified dextran inhibits smooth muscle cell growth in vitro and intimal in stent hyperplasia in vivo  Jean-François Deux, MDa,b, Sandrine Prigent-Richard, PhDc, Gisela d'Angelo, PhDd, Laurent J. Feldman, MD, PhDd, Edmond Puvion, PhDe, Delphine Logeart-Avramoglou, PhDf, Anne Pellé, MD, PhDd, Frank P. Boudghène, MD, PhDb, Jean-Baptiste Michel, MD, PhDd, Didier Letourneur, PhDa,c  Journal of Vascular Surgery  Volume 35, Issue 5, Pages 973-981 (May 2002) DOI: 10.1067/mva.2002.123093 Copyright © 2002 Society for Vascular Surgery and The American Association for Vascular Surgery Terms and Conditions

Fig. 1 Antiproliferative effect of E9 on SMC proliferation. A, Growth-arrested rat SMCs were released from G0 phase with addition for indicated times of 10% serum in absence (control, dotted line) or in presence of 100 μg/mL of E9 (□) or heparin (■). Cell numbers were determined, and values of growth inhibition are expressed as mean ± standard deviation of two separate experiments in triplicate. Native dextran (○) and anionic carboxymethylated dextran (♦) were inactive. B, Derived dextran (E9; □), native dextran (○), anionic carboxymethylated dextran (♦), and heparin (■) at indicated concentrations were incubated with SMCs for 5 days. Percent growth inhibition was determined with cell counting. Each point represents average ± standard deviation of two experiments performed in triplicate. C,3H-Thymidine uptake was assessed as reported in Materials and Methods section after 24 hours incubation of SMCs with serum (control) or serum + 100 μg/mL of E9 or heparin. Values of radioactivity in counts per minute (cpm) represent average ± standard deviation in one representative experiment performed in triplicate. D, Cell cycle distributions assessed with flow cytofluorimetry were determined 1 day after release from G0 block with serum addition (control) or serum + 100 μg/mL of E9 or heparin. Values represent average ± standard deviation in one representative experiment performed in triplicate. Statistical analysis for all figure: *P <.01 versus control. **P <.001 versus control. Journal of Vascular Surgery 2002 35, 973-981DOI: (10.1067/mva.2002.123093) Copyright © 2002 Society for Vascular Surgery and The American Association for Vascular Surgery Terms and Conditions

Fig. 2 Inhibition with E9 of MAPK tyrosine phosphorylation (A) and MAPK activity (B) in serum-stimulated SMCs. A, Quiescent cells were left untreated or were stimulated for 5 minutes and 1 hour with 10% serum (FCS) with or without E9. SMCs were lysed, Western blot tests were probed with monoclonal antiphosphotyrosine mouse antibody, and equal amounts of cell lysate proteins were analyzed for p42/p44 MAPK phosphotyrosine content. Densitometric analysis (arbitrary units) of presented lanes is reported. Results are representative of three independent experiments with significant (*P <.001) inhibition in presence of E9. B, Quiescent SMCs were left untreated (lane 1) or were stimulated for 5 minutes with 10% FCS (lane 2) or with 10% FCS + heparin (lane 3) or with E9 (lane 4). Detergent lysates were immunoprecipitated with anti-MAPK antiserum, and kinase activity was assayed against radiolabeled myelin basic protein (MBP) in immune complexes. Reaction mixtures were separated with SDS-PAGE (12%) and subjected to autoradiography. Position of 14 kDa marker is indicated. Densitometric analysis (arbitrary units) of presented lanes is reported. Results are representative of three independent experiments with significant (*P <.001) inhibition in presence of heparin or E9. Journal of Vascular Surgery 2002 35, 973-981DOI: (10.1067/mva.2002.123093) Copyright © 2002 Society for Vascular Surgery and The American Association for Vascular Surgery Terms and Conditions

Fig. 3 Binding and internalization of E9 into SMCs. SMCs were incubated for indicated times either at 4°C (○) or at 37°C (□) with radiolabeled E9. Cells then were washed, and amount of bound radioactivity was determined from cell lysates. Each point represents mean ± standard deviation of three values. cpm, Counts per minute. Journal of Vascular Surgery 2002 35, 973-981DOI: (10.1067/mva.2002.123093) Copyright © 2002 Society for Vascular Surgery and The American Association for Vascular Surgery Terms and Conditions

Fig. 4 Displacement experiments of SMC bound radiolabeled E9. Confluent cultures of SMCs were incubated for 4 hours at 4°C with radiolabeled E9 (10 nmol/L/dish) in presence of increasing concentrations of unlabeled E9 (□), heparin (■), native dextran (○), anionic carboxymethylated dextran (♦), or chondroitin sulfate (▴). Cells were washed, and amount of bound radioactivity was determined from cell lysates. Average of three values are indicated. Standard deviation for all points was less than 10% of mean value. Journal of Vascular Surgery 2002 35, 973-981DOI: (10.1067/mva.2002.123093) Copyright © 2002 Society for Vascular Surgery and The American Association for Vascular Surgery Terms and Conditions

Fig. 5 Internalization of E9. Representative electron micrographs of SMCs after autoradiography show E9 distributions when adherent cells were incubated at 37°C with radiolabeled E9 (1 μCi) for 15 minutes (A), 1 hour (B), and 6 hours (C). Black arrows show isolated (A) or grouped (B,C) radiolabeled E9 located next to plasma membrane and in endosomes. Silver grains were not found associated with nuclei. Original magnification, ×12,000 (A,C); and ×15,000 (B). N, Nucleus. Journal of Vascular Surgery 2002 35, 973-981DOI: (10.1067/mva.2002.123093) Copyright © 2002 Society for Vascular Surgery and The American Association for Vascular Surgery Terms and Conditions

Fig. 6 E9 inhibits SMC hyperplasia after balloon angioplasty and stenting. Photomicrographs with hematoxylin eosin staining of injured rabbit iliac arteries after 14 days in control animals (A) or in E9-treated animals (B). Cross-sectional analysis (Table II) revealed significant (P <.01) difference in lumen and intimal area within two groups. Original magnification, ×33 (A,B). Arrow indicates intima thickness. s, Stent; a, adventice; m, media; i, intima. Journal of Vascular Surgery 2002 35, 973-981DOI: (10.1067/mva.2002.123093) Copyright © 2002 Society for Vascular Surgery and The American Association for Vascular Surgery Terms and Conditions